Landing Light only works when switched on downstairs

[Nick230679]

I have just moved in to my new house and found there is an issue with the landing light. The switch upstairs only works when it is switched on downstairs. If you turn the downstairs switch off then the upstairs light does not work at all. Downstairs I have 2 separate switches units next to each other, 1 for downstairs light and 1 for upstairs light. The downstairs light switch has 3 red and 1 blue wire with 2 red and 1 blue all together. The switch next to this which operates the upstairs light has 1 blue wire going into L1 and 1 brown wire in com. The upstairs switch has a red wire going into com, 1 red wire going into 1W and 1 black wire going into 2W. As I have just moved house money is a little bit tight at the minute and I would like to sort this with out the cost of an electrician if possible but it all looks a bit messy to me. I will post pics tomorrow to hopefully make things a bit more clear. Any advice would be greatly appreciated

 

[Gerrydelasel]

Could just be corroded switch contacts. Try replacing the switch -they only cost a quid or two, if they're the standard white plastic ones.

 

[Echo the husky]

There needs to be a connection in all 3 terminals of the downstairs switch that controls the upstairs light.

There are many possible faults here, the quickest option to find and correct the problem is to call an electrician...

 

[ban-all-sheds]

Could just be corroded switch contacts.

¿Que?

 

[Nick230679]

Here are pics of the 2 switches the first pic being the downstairs and the second being the upstairs

 

[securespark]

Are you sure the first pic is not for the downstairs light?

It is wired as for a 1 way switch and the cabling does not match any that is in the upstairs switch.

If it is the landing switch, as Echo says there are not enough conductors.

If it is the landing switch, there must be a join somewhere between the old and new colours.

Could you post a pic of the other switch?

 

[Taylortwocities]

Smells to me of an older installation that did not originally have two-way switching. In any event, you won't be able to engineer two-way switching on that circuit, with only a twin and earth cable going away.

I am interested as to why there is twin and earth to that switch and an extra eatrh wire has been added (maybe to provide an earth to another nearby switch?)

 

[Nick230679]

There is another switch next to this switch which controls the downstairs light. I have attached a pic. When I took this off some of the wires just popped out of the terminal. I have put them back in and still have the same problem.

 

[ban-all-sheds]

Nick - basically you have to choose between Plan A and Plan B.

PLAN A:

• Learn how lighting circuits are wired.
  • //www.diynot.com/wiki/Electrics:Lighting
  • http://www.google.co.uk/search?q=uk+lighting+wiring+(basics+OR+101)
  • //www.diynot.com/wiki/Electrics:books
  • //www.diynot.com/wiki/Electrics:index
• Get a multimeter and learn how to use it.
• Identify which conductors are which at the switches and the light positions.
• Check for circuit continuity, switches working etc.
• Possibly install new cabling.
  
• Connect everything up properly.

PLAN B:

• Get an electrician.

There are some irresponsible people here who will tell you that there is a Plan C, which is to start trying different things without really knowing what's going on, hoping to get it working by luck, or by blindly following instructions to put-this-wire-in-that-hole without any idea as to why. Please don't listen to them - you must know what, and truly understand what, you are doing.

Electrical-installation-by-guesswork is a foolish idea.

There is no Plan C for anybody sensible.

 

[securespark]

View attachment 95862 There is another switch next to this switch which controls the downstairs light.

Now I'm confused!

Which switch is the downstairs switch for the landing light?

 

[chivers67]

I think BAS plan B looks best here

 

[ericmark]

From the colours clearly something has been modified so working out what has been done will be no easy task even for an electrician. We have had a few events which have caused problems between up and down stairs lighting over the last 30 odd years.
1) Some clever guy worked out how he could get away with just two wires between two way switches by borrowing a line supply from another switch.
2) We went to using silly inefficient lighting systems because the "looked good" the MR16 light pod was a major problem.
3) In order to supply the extra power required lighting was split into up and down stairs, however often unaware of 1).
4) RCD protection was added and then the splitting into upper and lower and the use of just two cores was found to have caused a borrowed neutral which needed correcting.
5) The electrician had not allowed for this in his quote so had to find some cheap way out of the problem.
To correct the problem there are many alternative methods.
A) Fit a new cable with three cores.
B) Dispense with a true two way system and have second switch only switch off when other switch was on.
C) Recombine upper and lower floors however this could contrive reg 314.1.
D) Use RF links between the two switches.
I am sure I have missed some of the options but it seems who ever found the shared neutral in your house selected B) however not only that clearly they have moved something and extended cables so you have a mixture of old and new colours. Even for an electrician this would be a head ache trying to work out what has been done, where a junction box is hidden and how to correct.
Personally I would use D) OK it means the is a 9 volt battery hidden behind one switch which may need renewing once a year but it is by far the easiest method to correct. And by time you include the cost of re-plastering when a new wire is installed likely the cheapest.

So the big question is can you do it as DIY? Well it is not impossible but not easy and clearly depends exactly which of the 1~4 and A~C applies. It's not going to be easy. So how do you rate your skills. If you have understood what I have said then maybe a chance, if not forget it.

 

[Gerrydelasel]

...

 

[Nick230679]

Many thanks for you help guys. Its obvious that something is not quite right. I think I'm going play it safe and get an electrician to look at it with the hope it wont create too much patching and plastering work. I have 3 young children so my priority is to make sure its safe.

 

[Gerrydelasel]

I have 3 young children so my priority is to make sure its safe.

It's not unsafe, just confusing.